This is an application to continue to provide training for six predoctoral candidates (previously four predoctoral candidates) and one postdoctoral candidate (previously two postdoctoral candidates) each year in a multidisciplinary program on HIV/AIDS leading to the M.S. (postdoctorals only) or Ph.D. degrees and for postdoctoral studies in epidemiology for those with a prior doctoral degree in epidemiology. The members of the multidisciplinary faculty include leading HIV/AIDS investigators from epidemiology, biostatistics, immunology, virology, clinical medicine, neurology, psychology, and behavioral sciences. In addition to a core program of courses in epidemiology, biostatistics, the biology of HIV, behavioral and public health strategies for control of HIV, health strategies for prevention of HIV infection, and surveillance, trainees will be required to take additional courses in other biologic, sociologic, and/or mathematical disciplines, research ethics and to participate in an ongoing seminar on HIV/AIDS. Trainees may also take elective courses from among the many additional courses in HIV/AIDS offered at UCLA. Trainees will develop theses, dissertations, and postdoctoral research in HIV/AIDS in collaboration with the interdisciplinary faculty of the program. Trainees will have the opportunity to work with investigators in a wide range of HIV/AIDS projects, including the Multicenter AIDS Cohort Study, the Pathogenesis of HIV/AIDS project, the Popular Opinion Leader Model study and behavioral studies aimed at vulnerable populations. They may develop research proposals using data from these studies or develop other dissertation topics. Trainees will be expected to publish at least one paper from their dissertation. Special efforts will be made to recruit qualified candidates from underrepresented minority groups.